This invention relates to a novel tool for sealing the water overflow outlet normally found in bathtubs and the like; and more particularly it relates to an adjustable tool for preventing flow of both water and air through a conventional tub overflow.
One of the major problems encountered by plumbers, when attempting to unplug the drain of a bathtub or the like, is to find some means for sealing off the overflow opening or outlet so as to prevent the escape of air through the outlet during a plunging operation on the drain. One known way of sealing the overflow is to employ a wet rag, which the operator attempts to hold with one hand over the strainer on the outlet overflow while attempting to plunger the tub drain with his or her other hand. In most conventional tubs the overflow opening is located adjacent the upper edge of the tub, almost directly above the tub drain, so that it makes it rather difficult for the operator to hold a wet rag over the outlet with one hand, while manipulating a plumber's aid with his or her other hand.
This problem is made even more difficult in the case of modern-day bathtubs, which often have a pivotal or rotatable valve operating member projecting from the center of the strainer or grate that covers the overflow opening. The presence of such member makes it almost impossible to seal the overflow airtight with a wet rag.
Heretofore efforts have been made to provide some means for sealing tub or sink overflows, but for purposes unrelated to the plunging of the drain. For example, U.S. Pat. No. 328,354 discloses the use of a rotatable, semi-circular valve or plate, which is mounted to rotate on the face of a perforated overflow strainer in such a manner that when the valve plate is rotated approximately 180.degree. in one direction it will tend to close the perforations in the strainers, and when rotated in the opposite direction it uncovers the perforations. The purpose of such a valve, however, was merely to prevent the escape of sewer gases out of the drain and into the overflow pipe when the associated basin or tub was not in use. There was absolutely no suggestion or concern with providing for the overflow an airtight seal which is capable of withstanding the violent bursts of air pressure which are developed when a drain pipe is being plungered.
U.S. Pat. No. 1,281,222 also teaches the desirability of employing a rotatable valve plate for selectively closing the ports in the cover plate or strainer for a tub overflow, but again, the patentee appparently was not concerned with providing an airtight seal which could withstand severe applications of air pressure, such as are encountered when a tub drain is being plungered. Moreover, these prior overflow valves were designed for specific installations, and therefore had utility only for the particular overflow drains for which they were designed. Furthermore, with today's modern tubs where the drain valve operating member is mounted for movement on the overflow strainer, the rotable cover valves as taught by these prior art references would be of absolutely no use, and could not be employed for the same purpose.
Accordingly, it is an object of this invention to provide a novel tool which can be used for sealing the overflow opening in any of a great variety of tubs, thereby to prevent any air from being exhausted through the overflow opening during the plunging of the main drain of the tub.
A further object of this invention is to provide a novel plumber's aid, which is relatively simple and inexpensive to manufacture, and which can be readily secured over the overflow of a conventional tub whenever it is desired to seal the overflow for the purpose of plungering the main drain of the tub.
A more specific object of this invention is to provide a novel, adjustable overflow seal, which is adapted to be releasably and sealingly secured over a bathtub overflow in place of the overflow strainer, and by the same screws used for securing the strainer to the tub.
Other objects of the invention will be apparent hereinafter from the specification, and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawing.